Is the big money getting nervous about stocks?

As the outlook for stocks becomes increasingly uncertain, there are signs that unlike during recent geopolitical crises, the big money is starting to get nervous.

"There is a sign that more fear is creeping into the market, and we've been doing the Greek dance for—God, I forgot how many years now. But what we're seeing is elevated levels in indexes that were not elevated in the past, so we're seeing people move into safer assets," said options expert Dennis Davitt of Harvest Volatility Advisors.

One indicator that stands out to Davitt is the comparison between corporate bond yields and Treasury yields. That spread has widened out considerably, meaning that investors are now demanding a greater return for riskier (albeit still quite safe) bonds.

Further, Davitt notes that the CBOE Volatility Index has begun to rise, meaning that investors are now willing to pay more for protection on the S&P 500. The credit and options market are thus both showing signs of fear, he said.

Yet according to Erin Gibbs, equity chief investment officer at S&P Capital IQ, the indicators that Davitt is examining merely show long-awaited signs of normality.

Regarding the spread between corporate and Treasury yields, Gibbs wrote to CNBC that, "Credit risk did become a more important factor in June, and now in July. But these are still very low spreads compared to the past three, five and 10 years, and is now just returning to a more normal historical range."

Similarly, while the VIX has jumped considerably, it is still below 20, which is often considered to be its historical mean.

"There is increased amount of fear in the markets, but it's because we are coming off of such incredible lows," Gibbs said.

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